The present invention relates to a shoe insert of a cross-linked polyolefin body foamed with closed cells, having a fiber layer arranged at least on the useful (or working) surface.
Shoe inserts of the type mentioned have been known for a long time. The inserts are distinguished by their good thermal insulation, their high adaptability to the human foot, their ability to damp vibrations and shocks in an excellent manner, and their inertness against aggressive liquids over long periods of time. The shoe inserts are easy to form and can be considered in this respect nearly ideal with respect to fitting orthopedic as well as fashionable footwear.
The moisture absorptivity and the permeability for water vapor of such inserts, however, are extremely low. In particular, if thin stockings of synthetic fiber materials are worn, disagreeable moisture and heat build-up can occur in closed footwear in the region of the sole of the foot after extended use. The desire therefore arose to develop insert soles of the type mentioned in such a manner that in case of heavy perspiration and after an extended period of time, moisture and heat build-up in the vicinity of the sole of the foot is prevented with high reliability. In achieving this aim, of course, it is essential that the earlier-mentioned advantages found in conventional inserts not be impaired in any way.